Fluiten Shaft Seal System – Check the Wear

A Fluiten shaft seal in two halves on the bench

We have just finished a complete shaft system on an 87′ Ferretti that had a unique shaft seal system from Italian manufacturer Fluiten.  The Fluiten shaft seals are part of the “face seal” family.  There are two main parts to any face seal system; the stationary body (right side of pictures) that is bolted to the stern tube and the “rotary” piece (left side) that is attached to the shaft and rotates.  The Fluiten relies on a pre-loaded spring in the stationary unit to keep constant pressure between the halves preventing the sea water from coming in.

During shaft maintenance all components need to be inspected.  With Fluiten shaft seals there is a small phenolic ring that is allowed to wear with time similar to a brake pad.  This version of the seal has the wearable ring on the rotating half.  However, other models from Fluiten have the wear ring on the stationary half.

The ring specification is 2 mm minimum before replacement.

Measure the wearable phenolic ring for proper thickness

Make sure your service provider is checking all of the manufacturer’s specifications.  Not all companies will go to this length.  Reassembling the boat with a wear item that is past its life is a disservice to you and potentially dangerous to your boating experience.